The workshop will take place at Tenbou (天坊 ) a traditional Japanese-style inn in Ikaho.
Website (Japanese): https://www.tenbo.com
The inn has hot springs and meals wil take place at the inn.
Ikaho is most easily reached internationally by flying to Tokyo and then taking a train or bus. See https://www.visit-gunma.jp/en/discover/destinations/ikaho/ for instructions.